Frame transferring mechanism and drive therefor



Oct. 13, 1936.

J. B. TIEDEMANN FRAME TRANSFERRING MECHANISM AND DRIVE THEREFOR Fi led Dec. 11, 1933 7 Sheets-Sheet 1 INVENTOR.

Julius B. Tiedemcmn ATTORNEY.

Oct. 13, 1936. J.- B. TIEDEMANN 2,057,351

, FRAME TRANSFERRING MECHANISM AND DRIVE THEREFOR Oct. 13, 1936. J. B. TIEDEMANN FRAME TRANSFERRING MECHANISM AND DRIVE THEREFOR 7 Sheets-Sheet 3 Filed Dec. 11

ww 0N Q INVENTOR. Julius B.Tz'eclemcmn ATTORNEY.

0a. 13, 1936. J. B. :TIEDE-MANN 2,057,351

FRAME TRANSFERRING MECHANISM AND DRIVE THEREFOR Filed Dec. 11, 1953 7 Sheets-Sheet 4 ATTORNEY.

J. B. TIEDEMANN FRAME TRANSFERRING MECHANISM AND DRIVE THEREFOR Oct. 13, 1936.

Filed Dec. 11, 1955 7 Sheets-Sheet 5 INVENTOR Julius B.T1'e Hermann ATTORNEY.

Oct. 13, 1936.

I J. B. TIEDEMANN FRAME TRANSFERRING MECHANISM AND DRIVE THEREFOR Filed Dec 11, 1955 7=SheetsSh eet e 4 INVENTOR. Julius B.Tiedemqnn ATTORNEY.

Oct. 13, 1936. J. B. TI EDEMANN 2,057,351

FRAME TRANSFERRING MECHANISM AND DRIVE THEREFOR Filed Dec. 11, 1935 INVENTOR.

Julius B. Tieclemann v MM ATTORNEY.

7 Sheets-Shget 7 Patented Oct. 13, 1936 l g UNlTED FRAME TRANSFER/RING MECHANISM AND DRIVE THEREFOR Julius B. Tiedemann, Milwaukee, Wis, assignor to A. 0. Smith Corporation, Milwaukee, Wis., a corporation of New York orrics Application December 11, 1933, Serial No. 701,842

19 Claims. (01. 74-44) 1.

The invention relates to improvements in tion and provide a smooth operation having the frame transferring'mechanism and drive thereproper timed" cycles for each function of the for,vand has found specific embodiment in an machine. apparatus employed in the manufacture of auto- Other objects will appear'hereinafter in conmobile frames. The system and apparatus for nection with the more detailed description of the 5 the manufacture of the frames constitutes a preferred embodiment of the invention illustrated semi-automatic plant embodying the general in the accompanying drawings. principles and features of United States Letters Figure 1 of the drawings is a transverse sec- Patent No. 1,397,020, issued to R. Stanley Smith, tion of the mechanism showing schematically and of several improvement patents all of which apparatus with which it is employed; 10

have been assigned to the A. O. Smith Corpora- Fig. 2 is a side elevation of the same mechation. nism; I I The present invention embodies an improve- Fig. 3 is an enlarged vertical section of the ment in frame transferring mechanism designed transfer mechanism, alone, in its raised position,

'15 to transfer the partially assembled frame strucon line 3--3, of Fig. 2;

tures to an assembling machine and to remove Fig. 4 is a similar sectional view of the transfer the assembled frame from the machine. mechanism in its lowered position;

The frames are partially assembled on conveyor Fig; 5 is a top plan view of oneend of the trucks and carried thereon to the transfer mechtransfer mechanism;

0 anism which removes the frame elements from Fig. 6 is a perspective view of the carriage a truck while retaining their relative positions showing. the clamping and lifting mechanism and deposits the elements in the same relative thereon; 7

p s ti n up th upp s of t assembling Fig. 7 is an enlarged detail sectional view taken w chine. This machine then assembles the eleon t n 1.4 of i 5; ments into a unitary frame and inserts rivets is top plan View f t drive for t in aligned openings in the several parts to term machine; porarily secure the elements together. The trans- Fig 9 is a Vertical Section on line f F 8 fer mechanism then removes the assembled frame Showing the drive for the carriage t f and and deposlts the Same upon conveyor truck certain of the cam drives in one position in the which subsequently transports the frame to a cycle of Operation;

plurality of stations where rivetingmachines are Fig is a section Similar to Fig 9 Showing caused to Set the Vanous S to complfite thedrive in the opposite position of operation in frame as more fully described in co-pending apthe cycle. plication Serial No. 501,301, filed December 10, 1930, by Birger T. Andren and Julius B. Tiedemann and assigned to the same assignee as the present case.

Fig. llis a vertical section on line 11-11 of 35 Fig. 8 showing the drive for elevating the carriage, and certain of the cam drives in one position in the cycle of operation; and The present invention constitutes a continuaa tion in part of co-pending application Serial No. Seaman t T 11 p t 40 501,302, filed June 10, 1930, by Birger T. Andren, 8 drlve the opposlte posltmn Opemmn m 40 Julius B.Tiedemann, Rudolph Furrer, and George the Cycle" Smith, and assigned to the same assignee The machine comprises, in combination with The principal object of the invention is to pro- Pom/8370f t ,transfer mefihamsmi vide a transfer mechanism for the purpose inblmg m Y Sup1?1y1ng and drnfmg tended which is simple in construction and which mechamsm and Smgle dnve for the Vanous 45 has few wearing parts, thereby making repair elementsd upkeep 1 expensive The conveyor system which supplies the parts Another object i t prgvide Such an apparatus to be assembled and carries away the assembled which will substantially increase the rate of frame may be of any Suitable design- That production and allow the employment of a much Shown in the drawings comprises two separa 50 shorter working cycle of operation. systems, one for bringing the parts to be assem- Another object is to provide a new type of bled to the machine, and the other for taking the drive for the transfer mechanism which will assembled frames away. The Specific voollslirllfir greatly increase the speed of operation and tion of these conveyor systems is described in co' which will also eliminate objectionable vibrae pending application Serial No. 501,301, filed De- 55 cember 10, 1930, by Julius B. Tiedemann and Birger T. Andren, referred to above.

In general, the conveyor for supplying parts to the machine comprises a right-hand set of parallel rails I and a left-hand set of parallel rails 2, each set providing a conveyor track upon which the trucks 3 are mounted for intermittent movement. The trucks 3 are transferred from one set of rails to the other at the ends of the rails by means of screw conveyors 4 operating from the same drive as that for the trucks on the track and providing a closed circuit or path for movement of the trucks.

The trucks 3 have individual adjustable supports 5 thereon for receiving the various frame elements in juxtaposed relation for assembly. As the trucks 3 pass intermittently along the rails I toward the assembly machine, workmen posted at the various stations along the rails place the several frame elements in position on the trucks. When the truck has received a complete frame and reached the end of the rails I, it is transferred laterally toward the assembly machine to the end of the set of rails 2, by means of the screw conveyors 4.

The frame transfer mechanism, as more fully described hereinafter, then picks up each individual frame element from the truck 3 and deposits it in the assembly machine, leaving the truck 3 empty. The empty truck then passes down rails 2 to the other end of the conveyor line where it is transferred to rails I by means of screw conveyors operating in the same manner as the screw conveyors 4 shown in the drawings at the end of the track adjacent the assembly machine.

In general, the conveyor for removing assembled frames from the machine is constructed Sim ilar to that just described and embodies two sets of rails 6 and I upon which a plurality of trucks 8 are mounted for intermittent movement. Screw conveyors 9, only one of which is shown, are also provided at the ends of the rails for transferring the trucks from one set to the other in the same manner as that previously described. The adjustable supports It] on each truck are adapted to receive the assembled frame and hold it during transport.

The conveyor systems, generally described above, may be constructed in any suitable manner, or eliminated and other suitable means provided for performing the functions described.

The assembling mechanism, with which the present invention finds its use, may have various details of construction depending upon the structure to be assembled. The mechanism illustrated diagrammatically in the drawings is for use in assembling automobile frames. Since the present invention is concerned with the transfer mechanism for supplying parts to the assembling machine and removing assembled frames therefrom, it will not be necessary to describe the complicated detail structure of the assembling mechanism which constitutes the subject-matter of application Serial No. 501,302, above referred to.

The frame transferring mechanism comprises, in general, a vertically movable track II, a horizontally movable truck I2 mounted on the track II, and transfer carriages I3 and I 4 carried by the truck.

The vertically movable track II comprises two parallel rails extending across the entire machine and across the sets of conveyor rails 2 and I, one at each end of the machine. Each rail is supported on two screw jacks I5 and the rails may be raised or lowered by operation of these jacks.

The rails are additionally supported by means of a plurality of air cushion cyclinders I6 which serve to cushion the downward movement of the rails and to facilitate raising the rails. In the preferred embodiment illustrated, four cylinders I6 are provided for each rail and are distributed about equally apart along the rail to properly balance the latter whether the truck I2 is at one end or the other of the rails.

The truck I2 comprises a rectangular frame having side bars I? and two tubular cross bars I8. Wheels I9 support the truck on the track I I.

The carriage I3 is suspended from one tubular cross bar I8 while the carriage I 4 is suspended from the other tubular cross bar I8.

The carriage I3 comprises two bars 2 3 and 2I extending parallel to the respective cross bar I8. The carriage bars 20 and 2I are suspended at each end by links 22 hanging from a yoke 23 fixed to the corresponding end of the respective cross bar I8. The mode of suspension is such that one bar 23 of carriage I3, for instance, is suspended from the yokes 23 on one side of the cross bar I8, and the other bar 2I of the carriage is suspended from the yokes 23 on the other side of the cross bar I 8, the bars tending to balance each other. The links 22 allow relative movement of the bars 20 and M toward and away from each other as will be explained hereinafter.

Carriage I4 is constructed similarly to carriage I3 and comprises two bars 24 and 25 suspended by means of links 26 from the fixed yokes 2'! on the other cross bar I8. The links 26 support the bars 24 and 25 for relative movement toward and away from each other as will be explained hereinafter.

The carriage I3 is adapted to carry the frame parts from a conveyor truck 3 and to deposit the parts upon the supports of the assembling machine. The carriage I3 is adapted to carry the assembled frame 28 from the assembling machine and to deposit it upon the supports ID of the truck 8.

Carriage I3 is provided with a plurality of clamps mounted on the bars 29 and 2!. The clamp 29 for carrying a cross bar, for instance, comprises a depending hook 30 mounted on bar 20 and adapted to hook into one end of the cross bar, and a similar depending hook 3I mounted on bar 2I and adapted to hook into the other end of the cross bar. The hooks 30 and 3I are controlled by relative movement of bars 20 and 2| toward and away from each other to cooperate in clamping or releasing the cross bar, as desired.

The clamps 32 for carrying the side bars comprise a pair of parallel transverse rods 33 and 34 having downwardly extending prongs at each end. Rod 33 is attached to bar 2!! while rod 34 is attached to bar 2 I. The prongs 35 at the righthand ends of the rods 33 and 34 are offset so that, as the carriage I3 is lowered over a truck 3, the prongs 35 on rods 33 will pass down. on the righthand side of the right-hand side bar while the prongs 35 on rods 34 will pass down on the lefthand side of the same side bar. Subsequent relative movement of the bars 20 and 2| toward each other will effect a clamping of the side bar between the prongs 35. One of the prongs 35 has a lateral extension 36 for passing under the side bar to prevent its accidental release from the clamp.

The left-hand side bar is clamped by means of prongs 37 mounted at the left-hand ends of rods 33 and 34 in a manner similar to the clamping of the right-hand side bar as just described.

right-hand side Thereafter the carriage is track l l, thereby lifting the frame elements from the truck 3. The carriage i3 is then moved laterally as illustrated in Fig. 3 to a position over the assembling machine by lateral movement of the truck I2 along the track Ii. Then the carria-ge i3 is lowered, as shown in Fig. 4, to position theseveral frame elements upon the supports of the assembling machine. The bars and 2! are then moved apart to open the clamps 29 and 32 and release the frame elements. The carriage is then raised and returned empty to a position over another truck 3 for picking up another group of frame elements.

During the transfer of a group of frame elements, they are maintained in the same predetermined relative position as provided in their placement on the trucks 3 .so that after their deposit on the supports of the assembling machine, they are ready for immediate assembly;

The adjustable depending hooks 38 mounted on bar 24 and similar hooks 39 mounted on bar 25 are adapted to cooperate in picking up an assembled frame 28 and carrying the same to the truck 8. As shown, hooks 38 mounted on the right-hand bar '24 are adapted to lift the lefthand side of the frame 28 while hooks 39 mounted on the left-hand bar 25 are adapted to lift the of the frame. By this arrangement the hooks 38 and 39 are adapted to pick upa frame when the bars 24 and 25 are moved away from each other and to release a frame when the bars 245 and 25 are moved toward each other.

Fig. 1 illustrates the carriage M over the assembling machine with the hooks'38 and 39 in'position for lifting the assembled frame 28. The next step is that of raising the carriage M and with it theframe 28 by raising the track H. transferred to theleft to a position over a truck 8 by lateral movement of the truck i2 along the track H. The track H is then lowered to effect a lowering of the assembled frame onto the supports IU of the truck 8. The hooks 38 and 39 are then separated to release the frame by moving the bars 24 and25 toward each other, and the carriage M is raised and returned empty to a position above the assembling machine. N

Since both carriages i3 and M are suspended from truck 92, the cycle of operation of each'carriage is identical with that of the other, so that both carriages are lowered simultaneously, one to pick up frame elements, and the other to pick up an assembled frame. raised simultaneously and transferred to the left where both are again lowered, this time to release their respective loads, after which they are again raised and transferred simultaneously back to position for lowering and loading.

By reason of thissimultaneous cycle of operation of the carriages l3 and I4, it is possible to provide a single means for driving all of the clamps and hooks in unison. This is accomplished by providing, at each end of the carriages, a tube 49 connecting the inner bars 2! and 24 and a longer tube El slidably mounted in the tube arm 52 having a Both carriages are then i 49 and connecting the outer bars 20 and 25. Relative longitudinal movement of the tubes 40 and 4| will effect a relative movement of the carriage bars 29 and 2! toward or away from. each other, as the case may be, and a relative movement of the carriage bars 25 and 25 away from or toward each other, as the case may be, the relative movement of bars 24 and 25 at any given time being opposite to that of bars 29 and 2|.

The relative longitudinal movement of each set of tubes 59 and i! is effected by a link 52 secured to tube 50, as at 53, and a link secured to tube 5!, as at 45. The inner ends of links 52 and M are pivotally secured to levers and A1, respectively, which are fulcrumed at their centers to the truck bars ii. The upper ends of the levers 49 and ll are connected by short toggle links 48 and 49, respectively, to the opposite ends of a rocker beam 59. The rocker beam 59 is secured to one end of a short pivot shaft 5! which extends through the side bar I! of the truck i2. An

roller 53 on its free end is attached to the outer end of the shaft 5!.

Operation of the arm 52 to the right as shown in Fig. i will effect a relative movement of bars 20 and 2! toward each other and of bars 24 and 25 away from each other to effect the desired clamping operations, while movement of the arm 52 to the left will effect a reverse movement of the bars and a release of the clamping members.

Operation of the arm 52 is effected only at the time when the truck I2 is lowered to either pick up a load or to release a load. That is, arm 52 is moved to the right when the truck is at the right-hand side of the machine and lowered ready to pick up a load, and the arm 52- is moved to the left when the truck is at the left-hand side of the machine and lowered ready to release its load. This movement of the arm 52 is effected by a horizontal reciprocating rod 54 having upright channel members 55 and 56 spaced horizontally thereon a distance equal to the lateral movement of truck I2. truck i2 is in its extreme right-hand position and lowered to pick up a load, the roller 53 engages in the channel 55. Movement of the rod 54 to the right then effects movement of the arm 52 to the right. When the truck i2 is in its extreme left-hand position and lowered to release its load, the roller 53 engages in the channel 56. Movement of the rod 55 to the left then effects movement of the arm 52 to the left.

The reciprocation of the rod 54 to the left or right at the required time in synchronism with the machine to obtain the desired clamping and release of frame members is obtained by suitable connections of the rod 54 to a link 5'! operated by the continuously. rotating cam disk 58, as will be explained hereinafter.

The arm 52 is, at all times during movement of the truck i2, locked either in its left or righthand position, in order to prevent accidental operation of the clamping members on'the carriages i3 and M and dropping of frame elements. This locking of the arm 52 is obtained by a vertical rib 59 on a cross head 69 at each end of the truck E2. The roller 53 is adapted to ride on either side of the rib 59 whenever the truck I2 is raised suificiently to disengage the right side of the rib until it is lowered into thev channel 55, and vice versa, when the roller 53 leaves the channel 56 on the left side of the rib When the 59, it will stay on the left side of the rib until lowered into channel 55.

The truck I2 is moved laterally by means of the cross heads which ride in horizontal guides 6|. Each of the side bars I1 of truck I2 has a guide member 62 provided with a groove 63 for receiving the vertical rib 59 on a cross head 69. Vertical movement of the truck I2 on rails II does not release the grooves 63 from the ribs 59, and so the lateral position of the truck I2 is controlled at all times by the cross heads 69.

The cross heads 69 do not move vertically, but are moved horizontally in their guideways GI by means of links 64 and crank arms 65 attached to a shaft 66 extending longitudinally of the machine at the right-hand side. A gear segment $1 is provided on the shaft 69 for driving the crank arms 65 through a predetermined rotary movement and reverse.

In order to facilitate acceleration and retardation of the cross heads 69 and lateral movement of the truck I2, an air-pressure cylinder 68 is provided at each side of the machine. A piston 69 operates in each cylinder to retard or accelerate the shaft 66 as its crank arms 65 are rotated to or away from their extreme positions in either direction. Each piston 69 is connected by a rod 19 to a crank arm H on the shaft 66. The air pressure in the cylinders is varied to suit different operating speeds and is preferably supplied from a suitable source of air pressure of large volume connected with the cylinders.

Having described the transfer mechanism in detail, the mechanism for driving the several parts will now be described. The drive mechanism may be divided into three general parts, although all are driven from a single common source of power so as to maintain synchronism of operation between the several parts. The three general parts of the drive mechanism are: the various cam drives for the assembling mechanism, for the rivet supply and driving mechanism, and for operating the carriage clamps; the crank drive for moving the truck I2 laterally; and the crank drive for raising and lowering the truck I2.

The several parts of the mechanism are driven from the main drive shaft 12 which is continuously rotated by a suitable source of power such as an electric motor or an engine (not shown).

The chief problems involved in designing the several parts of the drive mechanism, apart from that of properly timing and synchronizing the several parts of the entire machine, are to insure the least vibration possible and to obtain as rapid acceleration and deceleration of the several masses to be moved as possible consistent with smoothness of operation. The magnitude of these problems will be appreciated when it is realized that the total time for one complete cycle of operation of the entire machine is about seven seconds and that during that time many of the parts have to be accelerated and retarded twice as well as to have the requisite periods of dwell for operation of other parts.

The main drive shaft 12 is connected through suitable reduction gearing 13 to drive a shaft 14 upon which the cam 58 is mounted and which also operates the crank drive for moving the truck I2 laterally. The main drive shaft 12 is also connected through another train of reduction gearing 15 to drive a shaft 16 which operates the crank drive for moving the truck I2 vertically. The reduction obtained by gear trains 13 and 15 have the ratio of 2 to 1, thereby resulting in the driving of shaft 14 at one-half the speed of shaft 16. Shafts 14 and 16 are driven in opposite directions.

The cam drives for the assembling machine proper are mounted on shaft 14 adjacent the cam 58 and are illustrated only diagrammatically as at 11.

Cam disk 58 has a cam groove 18 in one side which coacts with roller 19 carried on a horizontal pivoted arm 89 near the free end thereof. The lever 51 is pivoted to the free end of arm 89 and extends upwardly therefrom. The upper end of link 51 is pivoted to the end of a crank 8| which rotates the horizontal stub shaft 82. The shaft 92, through suitable bevel gears 83, rotates a horizontal shaft 84 which, through bevel gears 85, rotates a vertical shaft 86 at each side of the machine. Each shaft 88 has a crank 81 at its upper end connected by means of the link 51 to the reciprocating rod 54.

The cam groove 18 is designed to raise the arm 89 and link 51 and to maintain them raised during approximately one-half of the revolution of shaft 14, and then to lower them during the remaining half of the revolution, to effect the desired closing and opening of the clamping elements on the carriages I3 and I4.

The crank drive for moving the truck I2 laterally on the track I I comprises, in general, the driving crank 89 attached to shaft 14, a plurality of arms pivoted on a common axis and connected together by means of toggle links which have their central pivots engaging a cam track, and suitable gearing driven by a gear segment on one of the arms.

In the construction shown, the crank 88 is connected to one pivoted arm 89 by means of a long connecting rod 90. A second arm 9i is pivoted at 92 in common with arm 89 and has its outer end conected by means of the toggle links 93 to the lever 89 at the point 94 where the connecting rod 99 is pivoted to the lever 89. The central pivot 95 between the toggle links 93 is provided with rollers 96 on each side adapted to ride in cam tracks 91 provided in the stationary side plates 98. The links 93 extend to the right from the arm 89 toward the crank 88, the significance of which will be pointed out later.

The arm 9! has an extension to the left of the lever 89 providing a connection for a second pair of toggle links 99 which connect arm M with the end of a gear segment I99 to the left of said arm 9I. The gear segment I99 is also pivoted at 92. The second pair of toggle links 99 have a central pivot I9I provided on both sides with rollers 1 I92 which ride in the cam tracks 91.

The gear segment I99 is connected by suitable gearing I93, shaft I94 and pinion I95 to drive the gear segment 61 on the shaft 56 to move the truck I2 laterally.

The problem in designing the above mechanism was to provide for the required dwell or rest period for the truck I2 at each end of its lateral stroke and at the same time obtain a rapid acceleration to maximum speed and retardation from such speed. To this end the cam track 91 was designed as shown with its central portion following substantially concentric to pivot point 92. The end portions of the cam track are curved differently, as will be pointed out hereinafter.

It will be noted that the dwell produced at the left end of the stroke is effected by a combination of or coaction between the crank 88, which is passing dead center, the toggle 99 which closes at this time, and the crank 65 which is also at dead vature of the right center. The curvature of the cam track 91 at its end determines the length of time of the dwell period beyond that normally obtained from the dead centers of cranks 89 and 95. It will be appreciated that truck I2 must be given sufficient time to lower and rise at the end of its stroke before resuming its return stroke.

The rapid acceleration of truck I2 is effected after a period of rest by the crank 98 passing dead center and starting to increase its power stroke, the toggle 99 becoming straightened and rapidly moving the segment I99 and the crank 95 passing its dead center and increasing its stroke. I Figure 10 illustrates the parts, shown in Fig. 9, at the other end of the stroke after retardation where the crank 89 is on its opposite dead center, the toggle 93 is closed by the end curvature of cam track 91 and the crank 95 is on its opposite dead center.

In order to obtain the full benefit of the closing of either toggle at'the end of the stroke, it is preferable that the other toggle remain fully open at such time. The drawings Fig. 9 show toggle 93 open and lying in the circular central portion of cam track 9'! when the toggle 99 is closed by the outer curvature of the left end of the cam track, while Fig. 10 shows the toggle 99 open and lying in the circular central portion of the cam track 91 when the toggle 93 is closed by the outer curend of the cam track.

The exact curvature at the ends of cam track 91 will depend upon the dimensions of the several parts and the dwell period desired at the ends of the strokes.

, The left end of the cam track9l is curved on a shorter radius concentric with the pivot point I99 on the gear segment I99, when the crank 99 is at the left, and the right end of the cam track 91 is curved on a radius concentric with the pivot point I91 on the arm 9| when the crank 89 is at the right. The proportion of length of the'cam track 91 constituted by the central curved portion largely determines the period of drive, while the proportion of the cam track 91 constituted by the curved portion at each end determines the period of fixed dwell at the respective end of the stroke.

During the time that the pivot rollers I92 are riding in the left-hand portion of the cam track 91, the toggle link 99 merely closes or opens, dependingupon the direction of movement of the arm 9!, and it does not at that time effect any movement of the gear segment I99. Furthermore, the gear segment I99 is locked against movement at this time by the left arm of the toggle 99 and the pivot rollers I92 riding in the cam track 91.

When the crank 89 is at its right-hand position and the toggle pivot rollers 99 are riding in the curved right-hand portion of cam track 91, the toggle link 93 functions merely to open and close without moving the arm 9| and at the same time locking the arm 9| against movement. The locking of arm 9| against movement effects a locking of gear segment I99 and prevents operation of the conveyor truck laterally.

The broken lines I99 in Fig. 9 illustrate the positionof crank 89 at which the pivot rollers I92 enter and leave the left-hand portion of cam track 91, thus illustrating the length of the dwell period in relation to the rotary movement of the crank 39, Similar lines could be drawn at the right side to illustrate the period of dwell when the crank 98 is at the right.

The shape of the cam track 91 in its central portion need not be concentric to the pivot point 92, but 'it;;may be flattened or it may be curved more sharply so as to control the rate of accelera tion and retardation of the driven element in any desired manner.

The crank drive for operating the screw jacks I and elevating or lowering the tracks I I is very similar to that just trucks I2 laterally. The drive is operated from crank I99 on shaft 19, which, as pointed out before, is rotated twice as fast as shaft I4 and in the opposite direction. The details of the mechanism are shown in Figs. 11 and 12.

described for moving the The essential difference between it and the mechanism just described lies in the fact that there is no crank corresponding to crank 95 for utilization of a dead center, and the period of dwell desired at one end of the stroke is longer than that at the other end. Furthermore, the central curved portion of the cam track is relatively short, thus providing a short working period for the drive. The dwell at the left-hand end is short, providing time only for operation of the carriage mechanism 39 to 39, inclusive, while the dwell at the right-hand end is long, providing time for the lateral transfer of the carriages.

Consequently, the cam track II9 as illustrated in Figs. 11 and 12 has a substantial curvature away from its circular path at the right end and only a reasonably small outward curvature at the other end, each end portion being concentric to the respective pivot point of the toggle link at that end as previously described with respect to Figs. 9 and 10. Since the detail mechanism for this drive is practically the same as for that described as to Figs. 9 and 19, it need not be described anew.

The gear segment III of this drive is connected through suitable gears II2, vertical shaft II3, gears II4, horizontal shafts IE5, and gears H9 to the vertical screw jacks I5 to drive the same.

The two crank drives are designed to cooperate in a manner providing overlapping of 'movement of the tracks II vertically and of the truck I2 laterally, as illustrated by the arrows in Fig. 3 showing the path of movement of the carriages I3 and I4. This feature gives each movement a lon er time of operation in a cycle of given time, and. allows the cycle of operation to be shortened.

The preferred embodiment of the invention has been described in detail above, but it will be understood that various embodiments may be employed within the scope of the accompanying claims and without departing from the spirit and objects of the invention.

I claim:

1. In combination with a device disposed for reciprocating movement, a crank arm connected to said device to effect reciprocation thereof, said crank arm being adapted to rotate through approximately one-half a revolution and return for each cycle of reciprocation of said device and to be at approximately dead center at each end of a stroke in the movement of said device, a drive shaft rotating at a constant speed, and means transmitting power from said shaft to said crank to drive the same and to produce a predetermined dwell in the operation of said crank at each dead center position thereof.

2. In combination with a device disposed for reciprocation, a drive shaft rotating at a. constant speed, a crank arm on said shaft disposed to drive said reciprocating device, and means interposed between said crank and said device for increasing the length of dwell of the latter between successive reciprocative movements when said crank approaches and leaves dead center and for a device disposed for reciprocation, a drive shaft rotating at a conefiecting a greater length between successive reciprocative movements when the crank is at one dead center position than when it is at the opposite dead center position.

4. In combination with a device disposed for cation in one direction being one-half of that in the other direction, a constantly rotating drive shaft, two auxiliary shafts driven in synchronism by said drive shaft, one auxiliary shaft rotating at one-half the speed of the other, a crank arm on each auxiliary shaft, the arm on the shaft having the higher speed of rotation being connected to reciprocate said device in the direction requiring the faster cycle of reciprocation and the arm on the lower speed shaft being connected to reciprocate the device in the other direction, and means interposed between each of said crank arms and the device for increasing the rate of acceleration and retardation in movement of said device during reciprocation in each direction.

5. In combination with a device disposed for alternate reciprocative movements in two different paths of reciprocation and at different cycle rates, a rotating drive shaft, two auxiliary shafts driven in synchronism by said drive shaft and at relative rates of speeds corresponding to the cycle rates of the reciprocative movements of said device, a crank arm on each of said auxiliary shafts successive reciprocative movements in each direction.

6. In combination with a device disposed for alternate reciprocative movements in two differrelative rates of speeds corresponding to the cycle rates of the reciprocative movements of said device, a crank arm on each of said auxiliary shafts and connected to reciprocate said device at the required speeds in the respective paths of reciprocation, and means interposed between each of said cranks and the device for eifecting a predetermined length of dwell of the device between successive reciprocative movements in each direction, the reciprocation of the device in each path of reeffected while said device is in a period of substantial dwell as to the other reciprocative movement.

'7. In combination, a device disposed for horizontal reciprocation and for vertical reciprocation through a cycle of lowering and rising at each end of the path of horizontal reciprocation, a constantly rotating crank connected to reciprocate said device horizontally, a second constantly rotating crank operating in synchronism with saidfirst crank and connected to reciprocate said device vertically, and means interposed between said during most of the cycle of vertical reciprocation of the device and to effect a dwell in the vertical reciprocation of the device between successive cycles of vertical reciprocation when the device is in its lowered positions and during most of the horizontal reciprocation of the device in each direction.

8. In combination, a device disposed for horizontal successive reciprocative movements.

9. In combination, a device disposed for horireciprocation, a constantly rotating drive shaft,

a crank arm on said shaft disposed to drive said centric path at one end.

12. In combination with reciprocation, a constantly a crank arm on said shaft a device disposed for rotating drive shaft,

arm, a second pivoted lever arm disposed for reciprocative rotary movement and connected to drive said device, a toggle link connecting said lever arms, and a stationary cam track for controlling the opening and closing of said toggle link during reciprocation of said first named pivoted lever arm to effect predetermined reciprocation of said second named pivoted lever arm, said lever arms having a common pivot point and said cam track defining a curved path substantially concentric with said pivot point at its central portion and curved outwardly therefrom at both ends.

13. In combination with a device disposed for reciprocation, a constantly rotating drive shaft, a crank arm on said shaft disposed to drive said reciprocating device, and means interposed between said crank arm and said device comprising a pivoted lever arm connected to receive reciprocative rotary movement from said crank arm, a second pivoted lever arm disposed for reciprocative rotary movement, a gear segment disposed for reciprocative rotary movement and connected to drive said device, a common pivot point for said pivoted lever arms and said gear segment, a toggle link connecting said pivoted lever arms, a second toggle link connecting said second named pivoted lever arm and said gear segment, and a stationary cam track for controlling the opening and closing of said toggle links, said cam track being designed to effect closing of the toggle link between said pivoted lever arms when said levers are at one end of their reciprocative movement and the crank arm is near one dead center position and to effect closing of said second named toggle link when said lever arms are at the other end of their reciprocative movement and the crank arm is near its opposite dead center position, said toggle links being maintained in substantially open position at all other times during reciprocation of the parts.

14. A device for transforming reciprocative movement comprising a pivoted lever arm disposed for reciprocative rotary movement and constituting the driving element, a second pivoted lever arm disposed for different reciprocative rotary movement than that of said first named lever arm and constituting the driven element, a common pivotal axis for said lever arms, a toggle link pivoted to said levers at their outer ends for connecting them in driving relation, a stationary cam track having a portion of its length concentric with said pivot and at a distance therefrom to maintain said toggle link open during its travel through said portion of the track and having another portion of the track of different curvature to effect closing of the toggle link during a portion of the stroke of said reciprocating arms, and means for causing the central pivot of said toggle link to follow the curved path of said cam track.

15. A device for transforming reciprocative movement comprising, a pivoted lever arm disposed for reciprocative rotary movement and constituting the driving element, a second pivoted lever arm disposed for different reciprocative rotary movement from that of said first named lever arm and constituting the driven element, a toggle link having its opposite ends pivoted to said levers for connecting them in driving relation and having a central hinge pivot, a stationary cam track extending along the path of said toggle link and lever arms, and means for causing the central hinge pivot of said toggle link to follow the path of said cam track, said cam track being constructed to effect opening and closing of said toggle at pre determined positions during reciprocation of the driving element to effect predetermined periods of reciprocative movement and dwell and predetermined acceleration and retardation of the driven element.

16. A device for transforming reciprocative movement comprising, a pivoted lever arm disposed for reciprocative rotary movement and constituting the driving element, a second pivoted lever arm disposed for different reciprocative rotary movement from that of said first named lever arm and constituting the driven element, said lever arms having a common pivotal axis, a toggle link having its opposite ends pivoted to said levers for connecting them in driving relation and having a central hinge pivot, a stationary cam track extending along the path of said toggle link and lever arms, and means for causing the central hinge pivot of said toggle link to follow the path of said cam track, said cam track being curved concentric to the pivot axis of said elements for a part of its length, and, at the end approached by said driven element, being curved concentric to the point of pivotal connection between the toggle link and the driven element, the first mentioned part of the cam track being located at a distance from its center that will maintain the toggle link open during movement therethrough and eiiect movement of the driven element, and the second mentioned part of the cam track being located to absorb reciprocative movement of the driving element in closing and opening the toggle link without moving the driven element.

17. A device for transforming reciprocative movement comprising, a pivoted lever arm disposed for reciprocative rotary movement and constituting the driving element, a second pivoted lever arm disposed for reciprocative rotary move ment and constituting the driven element, a third intermediate pivoted lever arm connected to said driving and driven elements by hinged toggle links, a stationary cam track extending along the path of reciprocation of said lever arms, and means causing the hinge pivots of said toggle links to follow said cam track during reciprocation of said arms, said cam track being curved in the central portion of its length to maintain said toggle links open during reciprocation therethrough, and being curved at the ends to effect closing of the toggle links as they approach their respective ends, thereby providing a period of dwell for the driven element at each end of the stroke of reciprocation of the driving element.

18. A device for transforming reciprocative movement comprising, a pivoted lever arm disposed for reciprocative rotary movement and constituting the driving element, a second pivoted lever arm disposed for reciprocative rotary movement and constituting the driven element, a third intermediate pivoted lever arm connected to said driving and driven elements by hinged toggle links, a stationary cam track extending along the path of reciprocation of said lever arms, and means causing the hinge pivots of said toggle links to follow said cam track during reciprocation of said arms, said cam track being curved in the central portion of its length to maintain said toggle links open during reciprocation therethrough, and being curved at the ends concentric on a radius equal to the end arm of toggle which operates at the respective end so as to absorb reciprocative movement of the driving element at the ends of its stroke by the closing and opening of the respective toggle links, the relative lengths of the central portion of the cam track and of its respective end portions being proportional to provide predetermined periods of reciprocative movements and dwells and of acceleration and retardation of said driven element.

19. In combination with a device disposed for reciprocation, a constantly rotating drive shaft, a crank arm on said shaft disposed to drive said reciprocating device, and means disposed between said crank arm and said device comprising a pivoted lever arm connected to receive reciprocative rotary movement from said crank arm, a second pivoted lever arm disposed for reciprocative rotary movement and connected to drive said device, a toggle link connecting said lever arms, and a stationary cam track for controlling the opening and closing of said toggle link during reciprocation of said first named lever arm to effect predetermined reciprocation of said second named pivoted lever arm, said pivoted lever arms having a substantially common pivot point and said cam track being disposed relative to said pivot point so that the Working portion of said cam track does not exceed a distance from said pivot point equal to the difierence in length of the longest arm and its adjacent link of the toggle and is at least a distance from said pivot point equal to the sum of the lengths of the shortest arm and its adjacent link of the toggle.

JULIUS B. TIEDEMANN. 

